Your API consumption is charged by rows of data of returned results. Each request consumes one row + number of results * price of each result.
For price of each result, please look it up in documentation for each function.
Most of requests will cost one row for the request itself + number of rows of returned results for the said request.
There are, however, additional costs for some features like "where" and "having".
Applications working through Integrations interface consume Integrations rows, thereby rows consumption will be determined under Ahrefs Subscriptions.
If you work directly with Ahrefs API without Integrations interface , API Rows will be consumed instead. API Rows consumption is determined under API Subscriptions.